You can ignore that message. Some internal functions use zlib, png and tiff but have no effect on OCR.
Your question (regarding leptonica and image types) indicates you are not familiar with building sw from source. In such case use tesseract installer from Mannheim University <https://github.com/UB-Mannheim/tesseract/wiki> Zdenko ut 3. 11. 2020 o 11:57 吳明恩 <smart5...@gmail.com> napísal(a): > Ok, I read bmp image to get result and show something errors, but i can > got image string. > Error message & command : > .\tesseract.exe .\test.bmp eng > Tesseract Open Source OCR Engine v4.1.1 with Leptonica > Warning: Invalid resolution 0 dpi. Using 70 instead. > Estimating resolution as 284 > Error in pixWriteMemPng: function not present > [image: error.png] > > > > And, I have a question how can i do build leptonica with any external > image library to can read jpg image? > > > 吳明恩於 2020年11月3日星期二 UTC+8下午4時41分59秒寫道： >> >> Environment >> Tesseract Version: >> 1.tesseract 4.1.1 >> 2.leptonica-1.76.0 (Nov 3 2020, 10:24:30) [MSC v.1927 LIB Release x64] >> 3.libtiff 4.1.0 >> Found AVX2 >> Found AVX >> Found FMA >> Found SSE >> Platform: Windows 10 64-bit >> >> I use tesseract.exe to OCR jpg to show something error, so i wnat do >> sothing? >> >> Error message & command: >> .\tesseract.exe .\Google.jpg eng >> Tesseract Open Source OCR Engine v4.1.1 with Leptonica >> Error in pixReadStreamPng: function not present >> Error in pixReadStream: png: no pix returned >> Error in pixRead: pix not read >> Error during processing. >> > -- > You received this message because you are subscribed to the Google Groups > "tesseract-ocr" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to tesseract-ocr+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/tesseract-ocr/e05a2eaf-6964-4e00-8410-09320c89f209o%40googlegroups.com > <https://groups.google.com/d/msgid/tesseract-ocr/e05a2eaf-6964-4e00-8410-09320c89f209o%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "tesseract-ocr" group. To unsubscribe from this group and stop receiving emails from it, send an email to tesseract-ocr+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/tesseract-ocr/CAJbzG8yRiqE_Tb7sk7hXnPuptwzxygxiQYvPC-bZA3ctSrjhWw%40mail.gmail.com.
